Technical information about springs
European Springs have been manufacturing coil springs since 1852 and these days, the group has 14 manufacturing facilities, each one of which is specialised for its market and its product range. All types of metal springs are designed and produced, with wire diameters from 0.03 to 65mm and with a flat thickness range from 0.5mm to 3mm.
The materials chosen here at European Springs are carefully selected to the appropriate application the type of spring will be needed for. Cold drawn stainless steel wire is generally used for simple design springs that will be used at normal temperatures. In some cases however, some spring projects require copper alloys as they cope with the demand for resistivity. Tungsten alloys are used for certain medical components to avoid corrosion and Quench and tempering steels is used for heavy springs.
The high tech and state of the art machinery we use here at European Springs allows us to use precision to create accurate results. In most cases, the chosen material is formed to the correct shape by plastic deformation when cold. But stampings and hot forming are also commonly used. We use the most modern machinery and processes available such as numerical control and automation machinery to ensure a perfect product is manufactured each and every time.
At European Springs, we use heat treatments in our spring production process to remove any negative residual stress from plastic forming. Heat treatment is also used to give the spring material maximum strength properties. The heat treatment can be divided into two categories, first case and second case treatment. In first case treatment, which we call stress relieving, the temperature and time a spring undergoes heat treatment is dependent on the type of material. In second case treatment, the methods of precipitation hardening or quenching and tempering are used in accordance with the material manufacturer's recommendations alongside our expert knowledge.
Grinding is a process used to make one or two flat ends on helical compression springs. Most of the time, our grinding is done dry, incorporating different deburring and chamfering methods; with air cooling for smaller springs and water spray for larger. This action of Grinding reduces the chance of the spring buckling, and gives it a neat and presentable finish.
Shot peening in simple terms is the action of subjecting a spring to a stream of small steel shots. This is in order to obtain compression stress in the surface layer, leaving it suitable for painting. We employ the use of specially catered machinery for shot peening here at European Springs. The process involves steel shots being accelerated at a high speed by a turbine wheel and are guided towards the springs. This intensive process is carefully controlled to ensure all the surfaces on the spring s receive equal treatment.
Presetting and load testing
In order to increase the performance of springs, some types are given controlled residual stresses into the material. This is made by a controlled plastic deformation, and in the spring trade, named pre-setting. This specific operation requires special machinery that subjects the spring to plastic deformation in an intended and controlled manner.
In some cases, when there is a spring load requirement and verification demands, the load is checked and documented in a final check. In cases where the load tolerances are tighter that the process capability, 100 % checks and sorting may be used, including sorting into force classes. These days, test machinery containing load cells, electronic length measurement and computers for digital registration is used to ensure controlled precision.
At European Springs, we pride ourselves on the wide range of surface treatments we have available. . The surface treatments used in the group are vibration deburring, washing/degreasing, dipping in oil, spraying with oil, zinc phosphating and powder coating. Other surface treatments are provided by subcontractors, please refer to the surface treatment section for more information.
Product identification and packing
We organise Product identification according to customer request and can be commonly identified by labelling packaging. Trade and industry standard barcodes can be provided if required. We pay close attention to detail meaning each individual spring is marked, with text or a number applied with an ink-jet printer but labels and engraving are also used.
The items we produce are packed to suit customer requirements. The most common packaging is a cardboard box and Europe pallet, but tape and reel, vacuum-formed trays, ordinary plastic bags and sterile bags are also commonly used. We also use bags with vapour phase inhibitors to prevent rust during transport and ensure safety during transit.
Since we control the entire process from design to manufactured result, we assume full responsibility for the product. This means that we also indemnify our customers if any such claims might be made.
All manufacturing units at European Springs have quality systems complying with ISO 9001-2000 that are certified by a third party. Companies that produce products for use in the motor industry are TF approved by a third party. All companies can manage project work in accordance with the APQP and PPAP requirements.
Quality - Environment
Environmental and quality work has high priority here at European Springs, with a programme for monitoring and improving the environmental aspects of our processes. Adding to this, we are proud to be certified under ISO 9001-2000 and ISO 14001.